Loop-takers for sewing machines



Sept. 4, 1956 R, JOHNSON v 2,761,402

LOOP-TAKERS FOR SEWING MACHINES Filed Aug. 27, l953 4 Sheets-Sheet 1 INVEN TOR.

WITNESS BY MMQW ATTORNEY S pt 4. 19 R. E. JOHNSON 2,751,402

LOOP-TAKERS FOR SEWING MACHINES Filed Aug. 27, 1955 4 Sheeis-Sheet 2INVENTOR. Ralph E. Johnson WITNESS F By I I I QMWW ATTORNEY Sept. 4,1956 R. E. JOHNSON 2,761,402

LOOP-TAKERS FOR SEWING MACHINES Filed Aug. 27, 1953 4 Sheets-Sheet 3Fig.3.

INVENTOR. WITNEQQ Ralph E. Johnson hw w 7 BY M ATTORNEY P 4, 1956 R. E.JOHNSON 2,761,402

LOOP-TAKERS FOR SEWING MACHINES Filed Aug. 27, 1953 4 Sheets-Sheet 4WITNESS ATTORNEY Unite fates atent but LOOP-TAIQERS FOR SEWING MACHINESRalph E. Johnson, Mountainside, N. J., assignor to The SingerManufacturing Company, Elizabeth, N. J a corporation of New JerseyApplication August 27, 1953, Serial No. 376,883

9 Claims. (Cl. 112-192) 2 Therefore, if it is desired to operate themachine at higher speeds, it is necessary to use a take-up other than acam take-up, such a one of the link-type, but in so doing, a portion ofthe thread-handling characteristics are sacrificed, which of course,adversely affects the quality of the stitching.

In accordance with the above, there has been provided by the presentinvention a supplemental means incorporated in the .improved loop-takerwhich will effect a thread-controlling action in conjunction with thetake-up and thus aid to approximate more closely the precise threadrequirements of the system and improve the stitching quality. In thismanner it is possible to obtain in a machine having a link take-up,stitching of a quality comparable to that of machines having a camtake-up, the

former of which machines is adapted to be operated at higher speeds thanthe latter and without the objectionable noise, vibration and wear ofthe latter.

As illustrated in the drawings, the present invention is embodied in asewing machine having a bed 1 including a bed-plate 2, a standard 3rising from one end of the bed ment of the invention which ishereinafter set forth in such detail as to enable those skilled in theart readily to understand the function, operation, construction andadvantages of it when read in conjunction with the accompanying drawingsin which:

Fig. l is a longitudinal vertical section view of a machine embodyingthe present invention.

Fig. 2 is a head end elevation view of the machine illustrated in Fig. lwith the face-plate removed to illustrate the underlying mechanism.

Fig. 3 is a bottom plan view of the bed of the machine illustrated inFig. 1 with the bottom cover-plate removed.

Fig. 4 is a detail view illustrating in top plan the shuttle carrier perse of the machine illustrated in Fig. 1.

Fig. 5 is a fragmentary detail view in perspective and The presentinvention relates to sewing machines and on an enlarged scale at theinner portion of the upper end of the shuttle carrier per se, with thecap in open position to show the underlying construction.

Fig. 6 is a front elevation view of the shuttle carrier of Fig. 4 withthe cap in open position.

Fig. 7 is a fragmentary sectional View taken substantially on the line77 of Fig. 6.

Figs. 8, 9, and 10 are fragmentary detail views of the stitchingmechanism of the machine illustrated in Fig. 1, showing the parts indifferent positions in the stitching cycle to illustrate the operationof the improved mechanism constructed in accordance with the presentinvention.

In sewing machines having a cam-type take-up, the thread-handlingcharacteristics can, by so designing the cam, be precisely controlled toprovide an optimum of thread as required by the needle and theloop-taker at the various points in the stitching cycle. However, a camtake-up is inherently noisy and generates forces which produceundesirable vibrations and tend to destroy the various elements of themachine as well as increase wear. For this reason, a machine employing acam take-up is necessarily limited to relatively slow operating speedsand even at lower speeds is relatively noisy and vibrates ohjectionably. To reduce vibration and noise, and thus to adapt themachine for higher speeds, a link take-up may be used. However, with alink take-up, the same precise degree of thread control cannot beobtained since the action of the links can be made only to approximatethe thread requirements of the stitching mechanism.

and a bracket-arm 4 terminating in a head 5, which bracket-arm extendsfrom the upper portion of the standard 3 and overhangs the bed 1. Theupper portion of the bracket-arm 4 is closed by a cover-plate 6 held inplace by screws 7, which cover-plate 6 includes an extension 8projecting forwardly of the machine and overhanging a light bulb 9 toform a shield for the same, as illustrated in Fig. 2. The open end ofthe head 5 is normally closed by a face-plate 10 pivotally mounted uponthe head 5.

The bed 1 includes a front wall 11, a rear wall 12, a standard-end wall13, and a head-end wall 14 all depending from the bed-plate 2, thehead-end wall 14 extending only a portion of the distance between thefront and rear walls 11 and 12 as best illustrated in Fig. 2, to provideclearance for elements of the bed-mechanism. A bed cover-plate 15 isprovided which is normally secured in place by a thumb-screw 16 threadedon a post 17 depending from the bed-plate 1. Rubber feet 18 are providedat both ends of each of the front and rear walls 11 and 12 upon whichthe machine normally rests when in operative position.

The machine is driven by an electric motor 19 carried by a bracket 20that is, in turn, fixed to the frame of the machine. The motor 19includes a shaft 21 carrying a worm 22 that meshes with a worm gear 23fixed to a main shaft 24 journaled longitudinally of the bracket-arm 4as in bearings 25 and 26. The usual hand-wheel 24a is fixed to thestandard end of the shaft 24. A socket 27 is provided which iselectrically connected to the light bulb 9 and the motor 19 (connectionsnot shown) and which is adapted to be connected to a source of power.

Vertically journaled for longitudinal reciprocation within the head 5 isthe usual resser-bar 28 carrying a presserfoot 29 at its lower end andbiased downwardly by the spring 30, which presser-bar can be raised by ahandlifter lever 31 that includes a cam surface 32 adapted to engage andraise a lug 33 fixed to the resser-bar 28. In the usual manner, uponraising the resser-bar 28, the lug 33 engages one arm of a bell-cranklever 34, the other arm of which contacts a tension-release plunger'35of a needle thread tension device 36 carried at the front of the head 5.I

A needle-bar 37 carrying a needle 38 at its lower end is journaledvertically in the head 5. Longitudinal reciprocation is imparted to theneedle-bar 37 by a link 39 pivoted at one end to a collar 40 fixed tothe needlebar and pivoted at the other end to a crank-pin 41 carriedbyan arm 42 fixed to a second crank-pin 43 that is,-in turn, carried by acounterbalanced crank 44 secured to the end of the main-shaft 24. Thereis employed a linktype take-up comprising a take-up lever 45 pivoted atone end to the crank-pin 43 and provided with the usual thread-eye 46 atthe other end, and an anchor-link 47 pivoted at one end to the head by apivot-stud 48 and pivoted at the other end to the lever 45 at anintermediate point thereof, as at 49.

Adjacent the point of stitch formation, the bed-plate 2 is provided witha throat-plate 50, see Fig. 3, and a slideplate 51. The work is fed pastthe stitching mechanism by a feeding mechanism including feed-dogs 52that extend through appropriate slots in the throat-plate 5d and intocooperation with the presser-foot 29. The feed-dogs are. mounted upon afeed-bar 53 pivoted at one end to an oscillating feed-advance rocker 54carried by a feed-advance shaft 55 journaled longitudinally of the bed 1as by cone-shaped end bearings 56 carried by lugs 57 depend ing from thebed-plate 2. Variable oscillation is imparted to the shaft 55 through apitman 58 connected at one end to a crank-arm 59 integral with theshaft, which pitman extends upwardly through the standard 3 to where afork 60 formed upon the opposite end thereof embraces a counterbalancedeccentric 61. At a point intermediate its ends, the pitman 58 carries aslide 62 that cooperates with a slot 63 in a conventional manuallyadjustable block 64 pivoted to the frame, by means of which blocktheoscillation imparted to the pitman 58 by the eccentric 61 uponrotation of the main shaft 24 is converted to variable reciprocation ofthe same, which in turn, imparts oscillation to the crank-arm 59 andshaft 55.

At its other end the feed-bar 53 is provided with a fork 65 thatreceives a crank-pin 66 carried by an arm 67 fixed to a two-partfeed-lift shaft 68 journaled longitudinally of the bed 1 as bycone-shaped end bearings 69 secured in lugs 70 depending from thebed-plate 2. Oscillation is imparted to the feed-lift shaft 68 through adetachable connection that is fully described in the copending patentapplication of R. E. Johnson et al., Serial No. 360,562 filed June 9,1953, now Patent No. 2,718,202, dated September 20, 1955. Briefly thisconnection cornprises a lateral arm 71 of a sleeve fixed to the shaft 68and apertured to slidably receive a coupling pin 72 that is slidablycarried by a block 73 loosely journaled on the shaft 68. The couplingpin 72 may be retracted by rotation of a conveniently accessible lever74 fixed to a vertically journaled rod 75 that carries a crank-pin 76 atits lower end, which pin 76 rides in a slot 77 integral with thecoupling 72 and thus retracts the same upon rotation of the rod 75.

The block. 73 includes a fork 78 which embraces an eccentric 79 on acountershaft 8!) that is journaled longitudinally of the bed 1 as bycone-shaped end bearings 81 fixed in lugs 82 depending from thebed-plate 2. The countershaft 80 may be oscillated by a pitman 83 thatis pivoted at its lower end to a crank arm 84 integral with thecountershaft and at its upper end is connected to a crank-section 85formed in the main shaft 24. Thus, upon rotation of the main shaft 24,oscillation is imparted to the countershaft 80 by the pitman 83 andcrank-arm 84, which effects oscillation of the block 73 through theeccentric 79 and fork 78. The block 73 may be selectively coupled to thefeed-lift shaft 68 by the coupling pin 72 Whereby the oscillation of theblock 73 may be imparted to. the feed-lift shaft 68.

The lower stitching mechanism comprises a shuttle housing 86 that is,secured to the head-end wall 14 of the bed 1, as by screws 87 passingthrough apertures 88 in the housing, see Fig. 6. To facilitate properorientation of the housing 86 there is provided a rib 89 on the rearface thereof that mates with grooves 90 formed in the face of the wall14. The opposite face of the housing 86. is machined to form adiscontinuous circular raceway including an inner side wall 91 and abottom wall 92. The outer side wall 93 of the raceway is formed as amachined boss carried by a hinged shuttle cap 94 that is pivoted to thehousing 86 in a manner more clearly evident in Fig. 7. This hingecomprises a slide 95 fitted through an aperture in the housing 86, whichaperture includes a cylindrical section 96 formed centrally of and for aportion of the length of a rectangular section 97 dimensioned to receivethe slide. The slide 95 is provided with a slot 98 to receive a spring99 that abuts at one end against the end of the slot 98 and at the otherend against the shoulder between the cylindrical and rectangularsections of the aperture. The shuttle cap 94 is apertured to receive ahinge pin 100 that extends through a reduced end portion 101 of the slot98. By the above hinge structure, not only can the shuttle cap 94 byswung to inoperative position but it and the outer side wall 9 3 of theraceway are resiliently urged into operative position.

The shuttle cap is maintained in operative position by a pair of clips102 formed from spring metal and substantially into U-shape and pivotedto the housing 86 by screws 103 which pass through the base of bothlegsthereof. The one leg 104 of the U-shaped clips is substantially longerthan the other to overlie the shuttle cap 94 and resiliently bias ittoward the housing 86. There are also provided thumb-pieces 105 forrotating the same, and stops 106 which engage the shuttle cap 94 tolimit rotation of the clips. To insure that the cap 94 will be seatedproperly with respect to the housing 86, and that the outer side wall 93of the raceway carried by the former will cooperate with the racewaywalls of the latter, there are provided a pair of pins 107 carried bythe cap 94 that are received within recesses 19% on the housing 86, seeFig. 6.

Seated within the raceway defined by the surfaces 91 and 92 of thehousing 86 and the surface 93 of the cap 94 is the bearing rib 109 of aconventional oscillating shuttle 110. The shuttle 110 carries the usualbobbin case 111 which is restrained against motion with the shuttle byan arm 112, the end of which is received within a notch 113 in theshuttle cap 94. Oscillation is imparted to the shuttle 110 by a shuttledriver 114 carried upon the end of a shuttle-shaft 115 that is journaledlongitudinally of the bed 1 as in bearing lugs 116 depending from thebedplate 2. At its opposite end, the shaft 115 is provided with an arm117 that carries a slide-block 113 at the end thereof on a crank-pin119. The slide-block 113 is fitted between the opposed tines of a fork120 integral with the countershaft 80, whereby oscillation is impartedto the shaft 115 upon oscillation of the countershaft 8t).

Secured to the upper portion of the shuttle housing 86 as by screws 121is a bridge-piece 122 having a needleaperture 123 bounded by opposedthread-controlling sideedges 123a and 1231), Figs. 4 and 5. Withreference to Fig. 4, it will be seen that the aperture 123 istransversely elongated in the direction of the side-edges 123a and 123band that the side-edges are joined at each end to define a closed slothaving a continuous edge completely around the same. However, it wouldbe equally satis factory if the side-edges were joined to define acontinuous U-shaped edge only at the end remote from the shuttle housing86-and the point where the needle 38 penetrates the bridge-piece or, inother words, adjacent the-cap 941 The opposite end of the aperture 123may be closed by the shuttle housing 86. The function of the side-edgesis primarily to perform a controlling action upon the needlethreadpassing through the aperture. With reference to Figs. 840, duringoperation of the machine the needle 38 comes down to initiate astitch-forming cycle. Upon penetrating the work W and passing throughthe needleaperture in the throat-plate 50, it passes through theaperture 123 in the shuttle bridge-piece 122 and down ad jacent the pathof travel of the loop-seizing point or beak 124 of the shuttle 110.After reaching its lowermost point of downward motion, the needle israised and in the usual manner casts a loop of the needle thread Tn intothe path of travel of the shuttle beak 124. At this time the shuttle isrotating under the action of the shuttle driver 114 with the beakadvancing toward loop-seizing position, or in the direction of arrow Ain Fig. 8. The beak 124 passes very close to the needle 38 and entersthe loop in the needle-thread Tn. As the beak 124 continues to advancein the direction of the arrow A the loop of thread thereon is forcedback on the beak of the shuttle, which position in the cycle isillustrated in Fig. 8. It will be noted that the needle-thread Tn atthis point in the cycle extends downwardly substantially vertically fromthe needle-aperture in the throat-plate 50 to the aperture 123 in thebridge-piece 122 and then at a comparatively large angle about theside-edge 123a toward and around the beak of the shuttle. Thus, sincethe thread is at an angle to the beak of the shuttle, it will be morerapidly urged backwardly upon the beak into its normal position whichmotion effects the usual loopspreading.

A further advantage of the closed needle-aperture is that atloop-seizure the thread is angled from the work, about the side-edge123a of the aperture 123 to the beak of the shuttle. This angled threadpath, in comparison with the normal shorter straight path from the workto the beak of the shuttle, effects a take-up action upon the thread,which action is equal to the difference between the length of thestraight thread path as heretofore used and that of the present angledthread path. It will be recalled that it is an inherent characteristicof a link takeup that the amount of thread available at this portion ofthe cycle exceeds the thread requirements of the stitching mechanism,which fact adds significance to this take-up action.

The thread-controlling action of the side-edges of the needle-aperture123 continues throughout the stitch-forming cycle, as illustrated inFig. 9 in which the shuttle is in an intermediate point in the stitchingcycle and still rotating in the direction of the arrow A. In thecustomary manner, upon reaching cast-off position, the needle-threadslides ofi the shuttle and completes its travel about the bobbin-case111, as the take-up begins to draw thread from the system. A relativelyshort amount of time is allotted to that portion of the cycle betweencast-off and the time the stitch is set in the work. During thisinterval, the take-up must perform its complete action including thewithdrawal of the needlethread from the shuttle through the opening thatappears between the heel 125 of the shuttle and the adjacent end of theshuttle-driver as the shuttle-driver is reversed from rotating theshuttle in the direction of stitch-formation to rotating the same in itsreturn motion. This withdrawal of the needle-thread from the shuttle atprecisely the time that the opening appears between the heel of theshuttle and the shuttle-driver, and before the shuttle has been drivenin the return direction, indicated by the arrow B, sulficient for therib 109 of the shuttle to enter the raceway in the casing and thus lockthe thread against withdrawal, is one of the most critical portions ofthe cycle. However, in a machine employing a link-type take-up, thethread in the system at that point immediately preceding reversal of theshuttle can only be made to approximate the optimum which is determinedby that amount which would be required so that any further action of thetake-up would tend to draw the loop of needle-thread out of the shuttle.In the present device, the use of the thread aperture 123 in thebridgepiece 122 again produces a thread-controlling action since thethread is angled from the work through the thread aperture 123 about theside-edge 123k and to the loop within the shuttle as seen in Fig. 10, atwhich time the shuttle driver 11 is acting to rotate the shuttle 110 inthe direction of the arrow B. This angle in the thread lead acts to takeup a certain amount of slack thread which brings the amount of thread inthe loop to approximately the optimum.

From the above, it will be seen that the side-edges123a and 12317 of thethread aperture 123 in the bridge-piece 122 not only effect athread-controlling action at both the time of loop seizure and at thetime the loop is Withdrawn from the shuttle, but also aidloop-spreading, and act to confine the thread throughout the stitchingcycle. In addition, it will be seen that the closed aperture minimizesthe possibility that dirt and other foreign matter might fall into theshuttle.

Referring to Figs. 5 and 6 in particular, the raceway for theoscillating shuttle which, as hereinbefore pointed out, comprises theside-wall 91 and bottom wall 92 formed in the housing 86 and the sidewall 93 formed on the shuttle cap 94, is formed to provide an increasedbearing surface over similar devices heretofore provided. To accomplishthis, the side wall 91 is angled toward the bottom wall 92 as at 126 andthe bottom wall 92 is angled toward the side wall 91 as at 127. Thus,there is formed a contacting point 128 that initially receives the beak124 of the shuttle as it passes the opening in the raceway. Thisconstruction produces an increased bearing surface over devices asheretofore provided without encroachment upon the clearance required forthe needle-thread particularly during loop-spreading. In addition itwill be noted that, with the use of an angled thread lead to the beak ofthe shuttle which more rapidly forces the needle-thread loop back on thebeak of the shuttle and thus decreases the angular travel of the shuttlerequired to perform this function, the possibility that the thread willnot be properly located back on the shuttle beak as it again enters theraceway is substantially reduced even though the bearing surface hasbeen increased. Of course, the increased bearing surface providessmoother and quieter operation and the provision of the point 128 forinitial contact with the shuttle reduces the possibility of collisionand also reduces shock to the shuttle. As best seen in Figs. 7 and 8,the side-edges and the end of the rib 109 at the heel 125 are beveled toprovide a smoother contact between the same and the end of the racewayopposite the angled point 128, at which end the side wall 91 and bottomwall 92 are formed at substantially a right angle as seen in Fig. 5. Aswill be evident, the heel 125 is the point of initial contact betweenthis end of the raceway and the shuttle upon return motion of theshuttle.

The increased bearing surface provided by the angled portions 126 and127 of the side wall 91 and bottom wall 92, also acts to hold theshuttle more firmly with its rib 109 in the raceway. It will be evidentthat, at that portion of the cycle during which the loop in theneedlethread is being withdrawn from the shuttle, the shuttledriverwhich is urging the shuttle to rotate in the direction of arrow B isinherently tending to urge the shuttle out of the raceway through thegap therein. Thus, since the bridge-piece 122 completely spans thethread-clear: ance gap in the raceway, the increased bearing surface,which more securely confines the shuttle to the raceway, tends topreclude the possibility of having the thread pinched and held by theshuttle against the bridge-piece by reducing the possibility that theshuttle might leave its raceway.

Numerous alterations of the structure herein disclosed will suggestthemselves to those skilled in the art. However, it is to be understoodthat the present disclosure relates to a preferred embodiment of myinvention which is for purposes of illustration only and not to beconstrued as a limitation of the invention. All such modifications whichdo not depart from the spirit of the invention are intended to beincluded within the scope of the appended claims.

Having thus set forth the nature of the invention, what I claim hereinis:

l. In a sewing machine having a frame including a bed and a headoverhanging the bed, cooperating stitchhaving an opening through whichsaid needle passes upon reciprocation thereof, and an element disposedbetween and in spaced relation to said work-supporting surface and saidshuttle, said element being provided with a relatively narrow elongatedaperture located within the body of said element and defined bythread-confining side edges between which said needle passes uponreciprocation thereof, said aperture having opposed threadconfining sideedges arranged parallel to the axis of oscillation of said shuttle.

2. In a sewing machine having a frame including a bed and a headoverhanging the bed, cooperating stitchforming mechanism carried by saidframe comprising an oscillating shuttle journaled in said bed and areciprocatory needle carried by said head and provided with aneedle-thread, a loop-seizing beak formed on said shuttle, a linktake-up carried by said frame and constructed and arranged to perform atake-up action on the needle-thread, a won-supporting surface on saidbed having an opening through which said needle passes uponreciprocation thereof, and an element disposed between and in spacedrelation to said work-supporting surface and said shuttle, said elementbeing provided with an aperture located within the body of said elementand defined by opposed thread-confining side-edges between which saidneedle passes upon reciprocation thereof, said loop-seizing beak beingconstructed and arranged to pass closely adjacent to the path ofreciprocation of said needle and to enter a loop formed in theneedle-thread during oscillation of said shuttle in stitch-formation,said loop being forced backwardly upon said beak and being spread aboutsaid beak as said shuttle is advanced, and the side-edges of theaperture in said element between which the needle-thread passes servingto confine the needle-thread to an angled path from the opening in thework-supporting surface, through the aperture in said element, and tothe loop about said beak as a loop of needle-thread is being seized, andto confine the thread to a similar angled path as the loop is withdrawnfrom the shuttle.

3. A shuttle mechanism for a sewing machine comprising a housing havinga discontinuous circular raceway with a gap therein, a shuttle having aperipheral bearing rib journaled in said raceway for oscillation of saidshuttle relative to said housing, the leading end of said bearing ibbeing transversely inclined to form a loop-seizing beak adjacent to oneof the side-edges thereof, a bridgepiece secured to said housing andspanning the gap in the raceway in spaced relation to the path of travelof said bearing rib across said gap, said bridge-piece having arelatively narrow elongated needle-aperture formed therein, saidneedle-aperture being spaced from the side edges of said bridge-pieceand being defined by a pair of parallel opposed thread-confiningside-edges arranged perpendicular to and extending transversely acrosssaid raceway.

4. A shuttle mechanism for a sewing machine comprising a housing havinga discontinuous circular raceway with a gap therein, a shuttle having aperipheral bearing rib journaled in said raceway for oscillation of saidshuttle relative to said housing, the leading end of said bearing ribbeing transversely inclined to form a loop-seizing beak adjacent to oneof the side-edges thereof, a bridge-piece secured to the housing andspanning the gap in the raceway in spaced relation to the path of travelof said bearing rib across said gap, said bridgepiece having arelatively narrow elongated needle-aperture formed therein, saidneedle-aperture being defined by a pair of parallel opposedthread-confining side-edges arranged perpendicular to and extendingtransversely across the planes defined by the side walls of saidraceway, said side-edges being joined to define a continuous U-shapededge at the end remote from said loop-seizing beak.

5. shuttle mechanism for a sewing machine comprising a housing having anopen-sided discontinuous; circular raceway with a gap therein andincluding a bottom Wall and a side wall, a 'displaceableshuttle-cap-including a raceway side-wall cooperating with said housingto close the open side of the raceway, a shuttle having a peripheralbearing rib journaled in said raceway for oscillation of said shuttlerelative to said housing, the leading end of said bearing rib beingtransversely inclined to form a loop-seizing beak adjacent to one of thesideedges thereof, the end of the raceway that initially receives saidloop-seizing beak as it passes the gap therein having the bottom walland side wall within said housing inclined toward each other to form acontacting point that initially receives the loop-seizing beak of saidbearing rib, a bridge-piece secured to said housing and spanning the gapin the raceway in spaced relation to the path of travel of said bearingrib across said gap, said bridgepiece having a relatively narrowelongated needle-aperture formed therein, said needle-aperture beingdefined by a pair of parallel opposed thread-confining side-edgesarranged perpendicular to and extending transversely across saidraceway.

6. A shuttle mechanism for a sewing machine comprising a housing havingan open-sided discontinuous circular raceway with a gap therein andincluding a bottom wall and a side wall, a displaceable shuttle-capincluding a raceway side wall cooperating with said housing to close theopen side of the raceway, a shuttle having a peripheral bearing ribjournaled in said raceway for oscillation of said shuttle relative tosaid housing, the leading end of said bearing rib being transverselyinclined to form a loop-seizing beak adjacent to one of the side-edgesthereof, the end of the raceway that initially receives said loopseizingbeak as it passes the gap therein having the bottom Wall and side wallwithin said housing inclined toward each other to form a contactingpoint that initially receives the loop-seizing beak of said bearing rib.

7. In a sewing machine having a frame including a bed and a headoverhanging the bed, cooperating stitchforming mechanism comprising anoscillating shuttle mechanism carried by said bed and a reciprocatorynetxlle carried by said head, a link take-up carried by said head andconstructed and arranged to perform a take-up action on a needle-thread,a work-supporting surface on said bed having an opening through whichsaid needle passes on reciprocation thereof, said shuttle mechanismcomprising a housing secured to said bed, said housing having adiscontinuous circular raceway with a gap therein, a shuttle having aperipheral bearing rib journaled in said raceway for oscillation of saidshuttle relative to said housing, the leading end of said bearing ribbeing transversely inclined to form a loop-seizing beak adjacent to oneof the side-edges thereof, a bridge-piece secured to said housing acrossthe gap in the raceway and disposed between and in spaced relation tosaid work-supporting surface and the path of travel of said bearing ribacross said gap, said bridge-piece having a relatively narrow elongatedneedle-aperture therein through which said needle passes uponreciprocation thereof, said needleaperture being spaced from the sideedges of said bridgepiece and being defined by a pair of parallelopposed thread-confining side-edges arranged perpendicular to andextending transversely across said raceway.

8. In a sewing machine having a frame including a bed and a headoverhanging the bed, cooperating stitchforming mechanism comprising anangularly movable loop-taker journaled in said bed and a reciprocatoryneedle carried by said head, said loop-taker comprising a housingcarried by said bed, said housing having an open-sided discontinuouscircular raceway with a gap therein and including a bottom wall and aside Wall, a displaceable cap including a raceway side wall cooperatingwith said housing to close the open side of the raceway, a loop-takerhaving a peripheral bearing rib journaled in the raceway for angularmovement of said looptaker relative to said housing, said needle beingadapted to enter said housing :during stitch-formation at substantiallya right angle to the axis of movement of said looptaker and adjacent toa needle-side of the raceway, the leading end of said bearing rib beingtransversely inclined relative to the center line of said bearing rib toform a loop-seizing beak that passes closely adjacent to the needleduring stitch-formation, the end of the raceway that initially receivessaid loop-seizing beak as it passes the gap therein having the bottomwall within said housing and the side Wall at the needle-side thereofinclined toward each other to form a contacting point that innitiallyreceives the loop-seizing beak of said bearing rib.

9. In a sewing machine having a frame including a bed and a headoverhanging the bed, cooperating stitchforming mechanism comprising anoscillating shuttle mechanism carried by said bed and a reciprocatoryneedle carried by said head, a link take-up carried by said head andconstructed and arranged to perform a take-up action on a needle thread,a work-supporting surface on said bed having an opening through whichsaid needle passes upon reciprocation thereof, said shuttle mechanismcomprising a housing secured to said bed, said housing having anopen-sided discontinuous circular raceway with a gap therein andincluding a bottom wall and a side wall, a displaceable shuttle-capincluding a raceway side wall cooperating with said housing to close theopen side of the raceway, a shuttle having a peripheral bearing ribjournaled in said raceway for oscillation of said shuttle relative tosaid housing, the leading end of said bearing rib being transverselyinclined to form a loop-seizing beak adjacent to one of the side-edgesthereof, the end of the raceway that initially receives saidloop-seizing beak as it passes the gap therein having the bottom walland side wall within said housing inclined toward each other to form acontacting point that initially receives the loop-seizing beak of saidbearing rib, a bridge-piece secured to said housing across the gap inthe raceway and disposed between and in spaced relation to saidworksupporting surface and the path of travel of said bearing rib acrosssaid gap, said bridge-piece being defined by a relatively narrowelongated needle-aperture formed therein through which said needlepasses upon reciprocation thereof, said needle-aperture having a pair ofparallel opposed thread-confining side-edges arranged perpendicular toand extending transversely across said raceway.

References Cited in the file of this patent UNITED STATES PATENTS166,071 Crecelius July 27, 1875 2,085,699 Kessler June 29, 1937 FOREIGNPATENTS 641,450 Germany Feb. 2, 1937 111,973 Switzerland r Oct. 1, 1925713,108 France Oct. 22, 1931 441,040 Great Britain Jan. 10, 1936

